You should first visit https://“raspberryPiAddress”
and
take note of the generated passwordsactivate your instance by hitting the activation button
this first run of init may take a while…(check the /var/log/ncp.log for …init done)
You will then be forwarded to the :4443 to further setup your instance, or you do this in the terminal by running sudo ncp-config .

The $pi@nextcloudpi is the Linux command line prompt
You log in with user pi an password raspberry initially
You can change the password with the passwd command